There’s more to being able to turn an irrigation well on and off remotely than meets the eye, according to Walcott, Ark., producer Clay Smith, who is participating in a study aimed at automating the operation of irrigation systems.

Smith and Joe Massey, research agronomist with the USDA-ARS Delta Water Management Research Unit at Arkansas State University, discussed the study in a presentation for the online Arkansas Soil and Water Education Conference.

“These are the intangible things that you can’t measure,” said Smith. “I can see this system working good for a field that is far away from home. On the map we displayed my house is probably a mile out of the picture. So I’m close, but even with me that close, I can use the remote on-off to do it from the house and save time.”

The remote function is contained in an app on Smith’s smartphone. “This system was not tied to a sensor even though I want to go that route, maybe in the future, using more automation to get a sensor to tell the well to turn on or off.”

The company installed the on-off system on the well, so it just required Smith to download the app and use it.

Smith, who farms with his father, Terry Smith, growing corn and soybeans, has also found the app to be helpful when punching holes in the plastic irrigation tubing many farmers use to irrigate those crops in the Mid-South.

“If you’ve ever done that by yourself, you know that the water can outrun you and make it to the end and blow out before you can get the holes punched,” he noted. “If I’m in a situation like that, I can shut the well off, get my holes punched, take my time, and then turn the well back on.

Storm damage

During thunderstorms, Smith can turn the pump off before the plastic pipe can be rolled over by the wind with the well still running, a situation that can take hours to repair after the storm system has passed through.

“When the thunderstorm is approaching, I can turn the well off,” he said. “If it missed us and didn’t rain, I can shut it off for 30 minutes and then turn it back. If the lights flicker at the house, I get a power-off text alert saying whatever field it was, the power is off. Then if it didn't rain, I knew I could turn it back on.

“When that would happen before, and I was doing it manually, I knew it usually meant I would have to let it run six hours longer the next day if we missed the rain.”

Dr. Massey discussed a 2020-2021 study using the aQuarius Farm Controls System on a farm in Mississippi County, Ark. The purpose of the study was to compare four levels of automation of crop watering on a field in rice in 2020 and soybeans in 2021.

“Again, we’re trying to find what is the optimal level of automation from a water use standpoint and getting farmer feedback on which of the systems that they like better, including some of the intangibles that Clay mentioned.”

Research study

In this study, the researchers compared 16 40-acre fields in one solid section.

“We were looking at the manual on and off, which is, again, just the way the farmer typically does it – on four fields (one well served four fields,)” he noted. “There was one with the manual on where, again, the farmer determined when to irrigate, but they set the timer on the aQuarius system to shut the well off at a predetermined time.

“We had what we called informed on and that’s where we had soil moisture sensors located at six, 12 and 18 inches in a spot in the upper third of the soybean field about 150 feet from the poly tubing. Those sensors would help us determine when to irrigate. Then, the farmer would use the timer-off feature.”

Researchers also had a close to full auto, informed on “where we were getting information from the sensors to determine the time of irrigation and then using the four auto valves to rotate around each of the four fields and, again, using the timer off. We used the Watermark soil sensors with a -70 centibar irrigation threshold.”

Massey said the researchers could have gone to a lower threshold, but with the four-field system they didn’t want to allow the first field to get too dry because it would take multiple days to get back around the four-field block.

“These fields have been perfect in every way for this study except they have a lot of variation, particularly with sand contents,” he said. “We know it will take a while to show differences in water use, assuming there will be, but the trend is the same that we’re seeing with Clay’s study.”